Hundreds of thousands of protesters took to city streets Monday with a renewed call to legalize the nation's undocumented immigrants--a chorus of voices more numerous and more forceful than at a historic rally in March that brought the issue home to Chicago.

U.S. Sen. Barack Obama, Cardinal Francis George and other dignitaries shared the dais at twin rallies at Grant Park and Union Park with anonymous activists who have built a movement largely from scratch. Speakers, in English and Spanish, drew cheers from a peaceful gathering awash in American flags and banners from every corner of the world, from Ghana to Guatemala.

"We have to change the world," said Jose Artemio Arreola, an Oak Park school janitor and key rally organizer, as he urged schoolchildren to pursue advanced degrees, parents to vote and legal residents to become U.S. citizens.

...At Grant Park, 'participants gleefully proclaimed that they had "buried" the Sensenbrenner bill, taking plastic noisemakers and beating a cardboard coffin labeled "H.R. 4437" and draped with the Mexican flag.

...Sidney Burrus, 44, looked on as marchers traveled slowly through the Loop. Burrus, an unemployed South Side resident, said he could appreciate people speaking up but said they mean increased competition for the same factory job he has been seeking for the last 18 months.

...Although much of the program was in Spanish, several unions turned out a rank-and-file of all races. These included UNITE HERE, which was formed when unions for the needle trades and hotel and restaurant workers merged, and the Service Employees International Union.

...At the Korean American Resource and Cultural Center, Korean and Filipino immigrants ate kim bap, a Korean rice roll, before boarding buses early in the morning.

..."What started out as a march born in fear ... has now become a movement of hope," Obama said. "People now recognize that this is not just about stopping bad things from happening but also about lifting up the good things that could happen if we all join together as Americans."